Kerr electro-optic properties of rare-earth doped Pb(Mg1/3Nb2/3)O3-PbTiO3 crystals

Pb(Mg1∕3Nb2∕3)O3-PbTiO3 (PMN-PT) crystals exhibit significant potential for applications in the electro-optical (EO) field, owing to their low half-wave voltage and high electro-optic coefficients, ease of miniaturization, and integration. However, the ferroelectric phase PMN-PT crystals exhibit a low extinction ratio due to light scattering and reflection by domain walls. In this study, high-transmittance paraelectric phase PMN-PT crystals were synthesized through compositional optimization and rare-earth ion doping. The optical and Kerr electro-optic properties of the crystals were systematically analyzed, considering the PT composition and doping with La3+ and Sm3+ ions. The La-PMN-8PT crystals demonstrated a transmission rate of 75%, a quadratic electro-optic coefficient of 4.28 × 10−16 m2/V2, an extinction ratio of 29 dB, and a half-wave voltage of 270 V. Additionally, the electro-optical performance of the crystals was evaluated over a range of temperatures, revealing excellent temperature stability in the La-doped crystals. These results highlight the promising potential of La-doped PMN-PT crystals for advanced electro-optical applications.